From 0b05eaa4b5de411437ff82c5b1f7b8fb45e0d4c1 Mon Sep 17 00:00:00 2001
From: Connor Olding <cloningdonor@gmail.com>
Date: Sun, 1 Aug 2021 07:09:21 -0700
Subject: [PATCH] document sum

---
 sh/sum | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/sh/sum b/sh/sum
index 56c1582..c8e50d0 100644
--- a/sh/sum
+++ b/sh/sum
@@ -4,6 +4,15 @@
 # YES_DASH
 
 sum() { ### @-
+    ### compute the summation of its arguments without forking processes.
+    ### this relies on the shell's built-in arithmetic operators.
+    ###
+    ### ```
+    ### $ sum 1 2 3
+    ### 6
+    ### ```
+    ###
+    ### **TODO:** consider renaming because sum(1) already exists.
     local sum=0
     for i; do
         : $((sum+=i))